Network access points using multiple devices

ABSTRACT

A system and method for providing access to a communication network includes providing a radio node comprising a first set of access point components including a radio component, and providing a physically separated controller node in communication with the radio node. The access point controller comprises a second set of access point components distinct from the first set of access point components, creating a distributed access point. A system controller may also be used to control at least one of the radio node and the controller node. The radio node, the controller node, and the system controller communicate over a communication link, such as a wireless or wired link.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.10/527,978 filed Oct. 19, 2005 now U.S. Pat. No. 7,835,328 (PublicationNumber US-2006-0140161), which is a National Stage of the PCTApplication PCT/US03/28840 filed Sep. 12, 2003 and published asW02004/025887 on Mar. 24, 2004, which also claims the benefit of U.S.Provisional Patent Application No. 60/410,537, filed Sep. 13, 2002.

BACKGROUND

In a large wireless network (meaning one that serves a large number ofusers and/or covers a significant area) multiple access points are oftendesired to provide connectivity to a backbone network for various clientdevices. The backbone network might be a corporate network (e.g., aLocal Area Network (LAN)), an extension of the Internet, or a “lastmile” connection from a Wide Area Network (WAN), which might includepublic spaces (e.g., libraries, shopping centers, airports, etc.). Aconventional access point has its core components integrated in a singledevice. These core components typically include an RF (radio) component,an amplifier, an antenna, a baseband module, a MAC (medium accesscontrol) module, a processor, memory, a LAN interface and so on, makingthe access point fairly complex and expensive. A technology specificchip or chipset typically provides lower level functions while upperlevel functions are sometimes provided by software running on aprocessor.

Access points are sometimes implemented using a single device design,sometimes called a “stand-alone unit.” However, with a single device,all-in-one-style access point there is no economy of scale. Each accesspoint costs the same to manufacture as the first, and there is noadvantage to be gained from modern power processors. Also, as a systemimplementing access points scales, certain aspects of the system becomemore complex. Because software processes or other processes governingfunctions such as multiple access management and/or mobility (e.g.,roaming or handing-off of a device from one access point to another) aresometimes distributed among multiple access points or othernetwork-connected processing entities, the system's complexity may growfaster than the number of access points.

Open industry interface specifications between radio and basebandblocks, as well as between physical (PHY) and MAC blocks of wirelessnetworking systems are the focus of current development in the field.For example, the JC-61 standards will initially focus on the WirelessLAN systems compliant to the IEEE 802.11 standard. Current developmentinitiatives do not address the remote connection of the PHY and MACblocks.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing components of a typical single-deviceaccess point.

FIG. 2 is a flow diagram showing three embodiments of distributed accesspoints resulting from various access point splits.

FIG. 3 is block diagram showing an example of a distributed access pointimplementation for one of the configurations of FIG. 2.

FIG. 4 is a block diagram showing an alternate example of a distributedaccess point implementation for one of the configurations of FIG. 2.

FIG. 5 is a block diagram showing an example of a distributed accesspoint implementation for one of the configurations of FIG. 2.

FIG. 6 is a block diagram showing an example of a distributed accesspoint implementation for one of the configurations of FIG. 2.

FIG. 7 is a block diagram showing an example of a distributed accesspoint configuration in an alternate embodiment of the invention, wherethree types of module are used.

FIG. 8 is a block diagram showing the distributed access pointconfiguration of FIG. 7 displayed using the architectural context ofFIG. 2.

In the drawings, the same reference numbers identify identical orsubstantially similar elements or acts. To easily identify thediscussion of any particular element or act, the most significant digitor digits in a reference number refer to the Figure number in which thatelement is first introduced (e.g., element 604 is first introduced anddiscussed with respect to FIG. 6).

DETAILED DESCRIPTION

The invention will now be described with respect to various embodiments.The following description provides specific details for a thoroughunderstanding of, and enabling description for, these embodiments of theinvention. However, one skilled in the art will understand that theinvention may be practiced without these details. In other instances,well-known structures and functions have not been shown or described indetail to avoid unnecessarily obscuring the description of theembodiments of the invention.

The headings provided herein are for convenience only and do notnecessarily affect the scope or meaning of the claimed invention.

It is intended that the terminology used in the description presentedbelow be interpreted in its broadest reasonable manner, even though itis being used in conjunction with a detailed description of certainspecific embodiments of the invention. Certain terms may even beemphasized below; however, any terminology intended to be interpreted inany restricted manner will be overtly and specifically defined as suchin this Detailed Description section.

I. Overview

Described in detail below is a system that provides for the division ofcomponents of a wireless network access point between two (or more)devices that are remote from each other and that can have a one-to one,many-to-one, one-to-one or many-to-many relationship between and amongstthemselves. This type of configuration is referred to as a “distributedaccess point” and includes multiple variations. Examples of distributedaccess points include the following:

-   -   A split between an RF (radio) layer and a baseband (physical)        layer of any wireless access point.    -   A split at the HCI (host controller interaction) layer in a        Bluetooth access point.    -   A split between the baseband layer and medium access control        (MAC) layer in an IEEE 802.11 access point.

The use of distributed access points allows a minimum or reduced amountof hardware to be deployed in the locations where users desire access,while processing power (and, thus, complexity) is concentrated in ancontroller node that can be scaled accordingly. This configuration canbe especially useful when the system is scaled to include a large numberof access points.

Components involved in the distributed access point include a radio nodeand a controller node, used interchangeably with the terms “access dot”and “access dot controller,” respectively. In some embodiments, thecontroller node corresponds to a collection of radio nodes in aone-to-many relationship, although a one-to-one relationship is alsopossible. A system controller may also be employed to control groups ofdistributed access points, including one or more radio nodes and theircorresponding controller nodes. Like the controller, the systemcontroller corresponds to one or more radio nodes (and theircorresponding controller nodes) in a one-to-many relationship. Thesystem controller functionality can be implemented in a distinct,centralized hardware component, such as a physical switch (e.g.,wireless switch). Alternatively, the system controller can be logicallycentralized, but implemented using a physically distributed hostingfunction incorporated into one or more distributed access points (e.g.,system control application running in every eighth radio node/controllernode combination).

To simplify installation of such a system, the devices may beinterconnected via standard (e.g., Cat-5) twisted pair wiring found inmost commercial buildings to provide power as well as communication. Thewired link might also use a fiber or coaxial cable. Alternatively, thedevices may be interconnected using some form of wireless link. Thislink might be an RF link such as a point-to-point relay RF technology orit might involve a broadcast RF technology. The wireless link might bean infrared link, ultrasonic, or other wireless interface.

In a broad sense, aspects of the invention are directed to a system andmethod for providing access to a communication network includesproviding a radio node comprising a first set of access point componentsincluding a radio component, and providing a physically separatedcontroller node in communication with the radio node. The access pointcontroller comprises a second set of access point components distinctfrom the first set of access point components, creating a distributedaccess point. A system controller may also be used to control at leastone of the radio node and the controller node. The radio node, thecontroller node, and the system controller communicate over acommunication link, such as a wireless or wired link.

The invention will now be described with respect to various embodiments.The following description provides specific details for a thoroughunderstanding of, and enabling description for, embodiments of theinvention. However, one skilled in the art will understand that theinvention may be practiced without these details. In other instances,well-known structures and functions have not been shown or described indetail to avoid unnecessarily obscuring the description of theembodiments of the invention.

II. Architecture

FIG. 1 and the following discussion provide a brief, general descriptionof a suitable computing environment in which the invention can beimplemented. Although not required, aspects of the invention aredescribed in the general context of computer-executable instructions,such as routines executed by a general-purpose computer, e.g., a servercomputer, wireless device or personal computer. Those skilled in therelevant art will appreciate that the invention can be practiced withother communications, data processing or computer system configurations,including: Internet appliances, hand-held devices (including personaldigital assistants (PDAs)), wearable computers, all manner of cellularor mobile phones, multi-processor systems, microprocessor-based orprogrammable consumer electronics, set-top boxes, network PCs,mini-computers, mainframe computers and the like. Indeed, the terms“computer,” “host” and “host computer” are generally usedinterchangeably, and refer to any of the above devices and systems, aswell as any data processor. Aspects of the invention can be embodied ina special purpose computer or data processor that is specificallyprogrammed, configured or constructed to perform one or more of thecomputer-executable instructions explained in detail herein. Aspects ofthe invention can also be practiced in distributed computingenvironments where tasks or modules are performed by remote processingdevices, which are linked through a communications network. In adistributed computing environment, program modules may be located inboth local and remote memory storage devices.

Aspects of the invention may be stored or distributed oncomputer-readable media, including magnetically or optically readablecomputer discs, as microcode on semiconductor memory, nanotechnologymemory, or other portable data storage medium. Indeed, computerimplemented instructions, data structures, screen displays, and otherdata under aspects of the invention may be distributed over the Internetor over other networks (including wireless networks), on a propagatedsignal on a propagation medium (e.g., an electromagnetic wave(s), asound wave, etc.) over a period of time, or may be provided on anyanalog or digital network (packet switched, circuit switched or otherscheme). Those skilled in the relevant art will recognize that portionsof the invention reside on a server computer, while correspondingportions reside on a client computer such as a mobile device.

The components or layers of a typical access point are shown in FIG. 1.The architecture can be divided into four main components or layers: anRF layer 102, a baseband (physical) layer 104, a medium access control(MAC) layer 106, and an access point (AP) software layer 108. Thesecomponents or layers may be implemented in task-specific dedicatedhardware and/or embedded software running on one or more processors,such as a CPU. Examples of dedicated hardware include the AtherosAR5001A chipset and the Cambridge Silicon Radio BlueCore. The BlueCoredesign uses a combination of dedicated hardware for the radio withsoftware running on an ARM processor that provides the baseband layer104 and a portion of the MAC layer 106 with the remainder of the MAClayer 106 and the AP software layer 108 running either on the same ARMor another CPU. Additional components may include a balun 110, anantenna switch 112, and one or more antennas 114.

In the architecture shown in FIG. 1, there are three split points atwhich the components or layers may be divided in accordance with variousembodiments of the invention. Each division or split results in twophysical devices: the radio node or “access dot” 200 and the controllernode or “access dot controller” 201 (shown in more detail in FIGS. 2through 8). At split point 1, between the AP software layer 108 and theMAC layer 106, the radio node 200 includes the AP software layer 108,and the controller node 201 includes the MAC layer 106, the basebandlayer 104, and the RF layer 102. At split point 2, between the MAC layer106, and the baseband layer 104, the radio node 200 includes the APsoftware layer 108 and the MAC layer 106, and the controller node 201includes the baseband layer 104 and the RF layer 102. At split point 3,between the baseband layer 104 and the RF layer 102, the controller node201 includes the RF layer 102 and the radio node 200 includes the APsoftware layer 108, the MAC layer 106 and the baseband layer 104. Whilenot shown, other combinations of components and splits are, of course,possible.

As further illustrated in FIG. 2, each distributed access pointdescribed above results in a distinct set of access point components orlayers for the radio node 200 and the controller node 201, and aseparate embodiment of the invention. A system controller 203, describedin more detail with respect to FIGS. 7 and 8, may also be used tocontrol groups of distributed access points. Configuration 202represents a conventional single unit access point architecture, andconfigurations 204, 206 and 208 represent different embodiments of theinvention with the physical separation being made at places equivalentto split points 1, 2, and 3 of FIG. 1, respectively. Each method ofdividing the circuitry between the radio node 200 and the controllernode 201 has advantages that depend on the components being used, thenature of the link, and the technology being served (e.g., wireless LAN,etc.). In general, configurations 204, 206, and 208 represent lower costalternatives to 202. The cost of each radio node 200 decreases incorrespondence to a decrease in complexity. For example, the radio node200 of configuration 204 is less costly to produce than the radio node200 of configuration 208. Because a system typically has multiple accesspoints, costs savings in a large system may be significant.

While less complex radio nodes 200 are less expensive, an increase inantenna intelligence of the radio node may be needed as more accesspoint functionality moves to the controller node 201. For example,configuration 204 has a relatively smart antenna 114 (or antenna array)when compared with configuration 208. Accordingly, configuration 204would be well suited for a “last mile” transport signals from a widearea network, as described in more detail below.

In the illustrated embodiment, configuration 208 is designed with adedicated connection to the controller node 201 over a cable (e.g.,Category 5 Ethernet cabling). Configuration 208 may use structuredpackets to facilitate communication between the radio node 200 and thecontroller node 201, and it may bridge packets from the radio node 200or may create Ethernet frames and IP payload packets. Configuration 208lowers the cost to deploy large networks because the radio nodes areeasily designed using commercially available chips and are less costlythan the conventional access points in 202. Configuration 208 isespecially useful in, for example, smaller enterprise networks wherededicated connections can be used without exceeding the Ethernetdistance limitation (100 meters).

Configuration 206 is designed to further lower costs by movingadditional functionality to the controller node 201 and furthersimplifying the radio node 200. In this case, costs are also lowerbecause dedicated connections can be replaced with tunnels that extendover an installed data network without regard for placement of the radionodes within specific Ethernet segments. These tunnels are used toencapsulate interface and exchange information between processing at theMAC layer 106 and processing at the baseband layer 104. Configuration206 is especially useful in, for example, medium to large Enterprisedeployments, where an in-place Ethernet network can be exploited forsignal transport between the radio nodes and the controller node 201.

Configuration 204 is designed to be the lowest cost for largedeployments, as the radio node 200 for configuration 204 consists of oneor more antenna/radio pairs (RF). Because tunnels are employed, andbecause the link is essentially a radio repeater, this configuration iswell-suited for non-line-of-sight deployments such as the last-mile froma WAN to a public or private site. The tunnels are used to carry adigitized form of RF data as a relay of a bit stream between the RFlayer 102 and the baseband layer 104 that handles either 802.11 orBluetooth baseband protocol. Configuration 204 is also useful inenterprise deployments that include a campus or large open space such asa manufacturing or warehouse site.

In some embodiments, including those where the baseband layer 104 andthe RF layer 102 are divided, such as with configuration 204, the radionode 200 may use a specialized circuit, such as a remote link driver 301(shown in FIGS. 3 through 7) to extend the bus (or wireless connection)between the baseband circuit and the RF circuit over a cable or wirelesslink. In the case of configuration 204, this may be done using a radiofrequency bit stream in a protocol stack tunnel between baseband layer104 and an RF layer 102. The resulting signal may be transmitted overcoaxial cable or over the air as an RF signal. In this way, thecontroller node 201 (the module containing the baseband layer 104) andthe radio node 200 (the module containing the radio) can be separated bya distance. FIGS. 3 and 4 illustrate examples of configuration 204 builtusing available chipsets.

With respect to configuration 206, the remote link driver 301 may carrya digitized radio frequency baseband signal encapsulated in a packetstructure through a tunnel for transport over structured wiring or viaRF over the air. This tunnel link could operate over a network withrouters and switches and, thus, dedicated connections may not berequired.

With respect to configuration to 208, the remote link driver 301 couldbe implemented using a structured packet technique (for example,Ethernet framing and IP packets with standard headers, or 802.11 packetsencapsulated in IP) and a dedicated link to the controller node 201.

Tunnel links described with respect to configurations 204 and 206 can beeither connection-oriented or connection-less communication methods thatprovide data encapsulation and transport mechanism between select accesspoint layers. Where tunneling is used, an associated control plane maymanage tunnel functionality and handle configuration/discovery fortunnel communications.

In some embodiments, tunnels may be implemented as Layer 2 (Ethernet)proprietary frames employing a specialized or standard protocol. SuchLayer 2 frames traverse an Ethernet network through Ethernet switches,bridges and hubs. In an alternate embodiment, tunnels may be implementedas Layer 3 (IP) TCP/IP frames, where connection-oriented TCP/IPprotocols are used between devices to convey information exchange.

FIG. 3 is an example implementation of configuration 204 using variouscommercially available chip sets, configured for 802.11. In theillustrated embodiment, an Atheros chip set is used to construct anradio node 200 containing the RF or radio stage, and an controller node201 containing all the other elements of an 802.11 access point. Inparticular, the two chips in the illustrated Atheros chip set are theAR5111 chip 302, which contains the majority of the RF circuit and theAR5311 chip 304, which contains the baseband layer 104 and the MAC layer106.

Although not illustrated for purposes of clarity, the AR5311 chip 304includes an integrated 32-bit MIPS R4000-class processor, various serialinterface devices (UARTS and LAN controllers), a local bus interface,and technology that automatically selects the data rate,error-correction mode, radio channel, power-management method andsecurity. The AR5311 chip 304 performs receive and transmit filtering,frame encryption and decryption, and error recovery as defined in IEEE802.11a. It also handles the host CPU interface and many other accesspoint-related functions as defined in IEEE 802.11a.

The AR5111 chip 302 provides IF conversion, support for the IEEE 802.11astandard, integrated power amplifiers, and low-noise amplifiers. TheAR5111 302 implements the orthogonal frequency division multiplexingscheme that is the radio encoding scheme for 802.11a and supports allIEEE 802.11a data rates from 6 to 54 Mbps. The AR511 chip 302 alsoimplements forward error correction, signal detection, automatic gaincontrol, frequency offset estimation, symbol timing, and channelestimation.

Signals between the AR5111 chip 302 and the AR5311 can both be analogand digital. The analog signals carry the data signal between the radionode 200 and the controller node 201. The digital signals are controllines. An ADC (analog-to-digital converter) 306 and a DAC(digital-to-analog converter) 308 are built in to the AR5311 chip 304.The remote link driver 301 functions to encode, transmit, andreconstruct these signals over the link medium. A typical implementationwhere the link is 4-pair Cat-5 twisted cable might include a balun, suchas the balun 110 of FIG. 1, to send the analog signals over the firsttwo pairs of cable (one in each direction). Parallel-to-serial andserial-to-parallel converters in conjunction with line drivers can beused to send digital control signals over the second two pairs of cable.

FIG. 4 is a suitable implementation of configuration 204 using a SiliconWave SiW1701 radio modem 402 and a Baseband IP module 404 configured forBluetooth. The SiW1701 RF radio modem 402 is optimized for Bluetoothwireless communications. It combines a 2.4-GHz radio transceiver andGFSK modem with digital control functions. The interface to the SiW1701is digital and may be designed to interface with Bluetooth baseband ICsfrom Silicon Wave and other manufacturers.

The Silicon Wave Baseband IP module 404 provides the Bluetooth linkmanagement and control functions and is offered as a reusable IP blockfor microcontroller based SOC (system on a chip) designs. In combinationwith the SiW1701 radio modem 402, it provides a complete solution forBluetooth applications. The Silicon Wave Baseband IP module 404implements real-time lower layer protocol processing as called for inthe baseband section of the Bluetooth Specification version 1.1. Thishardware performs the logical protocol processing within the unit thatenables the host to communicate over a Bluetooth link. Real-timefunctions such as frequency-hopping, burst timing, synthesizerprogramming, and clock synchronization are implemented in the hardwarealong with Bluetooth transmit and receive data functions.

The Silicon Wave Baseband IP module 404 also provides functionsassociated with the baseband layer 104 including forward errorcorrection, cyclic redundancy checking, scrambling and unscrambling ofthe signal, header error correction, encryption, and decryption. Thesefunctions are split between hardware blocks such as a Silicon WaveBluetooth Controller 406 within the Silicon Wave Baseband IP module 404and firmware running on an embedded ARM processor 408.

As with any access point, the radio node 200 shown in FIG. 4 may becalled on to perform certain higher-level functions, depending on themode of operation. The Bluetooth LAN Access Profile requires a PPP(point-to-point protocol) link to be created on top of the Bluetoothlink. The PPP link allows the access point to provide network services(i.e., LAN access) to the client device. The higher level functions runon an access point CPU 410 which may or may not be the same CPU as theARM processor shown in the Silicon Wave Baseband IP module 404. The twoprocessors (the ARM 408 and the block marked CPU 410) are shownseparately for clarity in distinguishing the functions.

III. Alternative Embodiments

While certain embodiments have been described above, alternativeembodiments may be implemented, some of which are described with respectto FIGS. 5 through 8.

FIG. 5 illustrates an embodiment of a distributed access point forBluetooth that reflects the architecture shown in configuration 206 ofFIG. 2. The baseband layer 104 and the RF layer 102 are in the radionode 200, and the MAC layer 106 and the AP software layer 108 are in thecontroller node 201. With this configuration, the control and datasignals from the Bluetooth controller block are sent over the link to anARM processor 502, which is resident in the controller node 201. Thisembodiment allows the ARM processor 502, similar to the ARM processor408 in the Silicon Wave Baseband IP module 404 of FIG. 4, to be combinedwith the other CPU 504. In the illustrated embodiment, part of thecomponents that comprise the Silicon Wave Baseband IP module 404 of FIG.4 are located in the radio node 200. These are the hardware functions.The firmware functions of the Silicon Wave Baseband IP module 404 ofFIG. 4 are located in the controller node 201. The remote link driver301 replaces the ARM processor bus (AMBA 2.0) connection between aBluetooth controller block (not shown) and the ARM.

FIG. 6 illustrates a Bluetooth-configured embodiment that reflects thearchitecture of configuration 208 of FIG. 2. The AP software iscontained in the controller node 201, and all other access pointfunctions are contained in the radio node 200. This embodiment reflectsa split at the host controller interaction layer (HCI) of a typicalBluetooth access point. A complete Silicon Wave Baseband IP module 404,is located in the radio node 200, together with the SiW1710 radio 402,both shown previously with respect to FIG. 4. In this configuration, theradio node 200 would be a client of the access point controller 201 CPU601.

FIGS. 7 and 8 illustrate an embodiment of the invention as it applies tomultiple components in a system. Referring to FIG. 7, the componentsfrom FIG. 4 are used to create three modules: the radio node 200, thecontroller node (intermediate controller) 201, and the system controller203, previously shown with respect to FIG. 2. FIG. 8 shows thisembodiment in the same architectural context as FIG. 2. In theillustrated embodiment, the system controller 203 enjoys a one-to-manyrelationship with multiple distributed access points, and providesfurther distribution of functions through a hierarchy. For example, asshown in FIG. 8, the system controller may include the AP software layer108, the controller node may include the MAC layer 106 and the basebandlayer 104, and the radio node may include the RF layer. More generally,however, there can be a one-to-one, one-to-many, many-to-one, ormany-to-many relationship between and among radio nodes 200, controllernodes 201, and system controllers 203. Likewise, the functions providedby any of these components can be distributed throughout the variousdevices, or combined into a single component at any level.

The system controller 203 handles system-related functionality andcommunication with one or more distributed access points. The systemcontroller 203 functionality can be implemented in a distinct,centralized hardware component, such as a physical switch.Alternatively, the system controller can be logically centralized, butimplemented using a physically distributed hosting function incorporatedinto one or more radio node/controller node combinations, such as asystem control application running in select radio nodes or controllernodes (depending on how they are split). In this case, there may becross-communication between radio nodes 200 and/or controller nodes 201,via, for example, tunneling techniques, such as those described withrespect to FIG. 2.

System-level functions performed by the system controller 203 caninclude configuration (e.g., Web/CLI/SNMP/proprietary), handling ofnetworking protocols (e.g., SNTP, DNS, DHCP, etc), and RF management(e.g., RF channel analysis, interference avoidance, performanceoptimization, thorough coverage, transmit power and receive sensitivitycontrol, etc). Other system level functions include control fordistributed topology (e.g., discovery, state machine control, reporting,management and monitoring, etc). The system controller 203 may alsohandle statistics gathering and monitoring, security policies (e.g.,authentication authorization, access control, etc.), VPN and VLANmanagement/distribution, and firmware and configuration distribution. Ofcourse, the system controller may handle other functionality, or mayshare the above functionality with other components of the system.

In the illustrated embodiment, the controller node (intermediatecontroller) 201 handles communication with one or more radio nodelayers/components (depending on implementation) and is the appropriatecontrol mechanism for distribution of RF-based applications. Thecontroller node 201 may also handle baseband protocols (different for802.11 and Bluetooth), baseband protocol configuration, monitoring,reporting MAC Layer protocols, data transfer, interworking functions,protocol conversions, security enforcement (e.g., encryption,authentication, VPN and VLAN support), etc. Like the system controller203, the controller node may handle other functionality, or may sharethe above functionality with other components of the system. Althoughnot shown in FIG. 7 or 8, multiple controller nodes 201 may be used in asimilar configuration, while still allowing the distribution of certainfunctions while retaining a high-level of flexibility as to the type offunctions that may be distributed. If not co-located with the systemcontroller 203, the control node 201 also handles communication with thesystem controller.

The description of embodiments of the invention is not intended to beexhaustive or to limit the invention to the precise form disclosed.While specific embodiments of, and examples for, the invention aredescribed herein for illustrative purposes, various equivalentmodifications are possible within the scope of the invention, as thoseskilled in the relevant art will recognize. For example, while blocks orfunctions are presented in a given order, alternative embodiments mayimplement blocks or perform functions in a different order, orblocks/functions may be implemented/performed substantiallyconcurrently.

The teachings of the invention provided herein can be applied to othersystems, not only the system described herein. For example, theteachings of the invention can be applied to the systems described incommonly assigned U.S. patent application Ser. No. 10/052,910, filedJan. 18, 2002, entitled “Link Context Mobility, such as for use inWireless Networks,” PCT Application No. US02/13880, filed May 2, 2002,entitled “Wireless Base Station Neighbor Discovery,” U.S. patentapplication Ser. No. 10/139,609, filed May 2, 2002, entitled “WirelessSystem Base Station to Base Station Synchronization,” U.S. patentapplication Ser. No. 10/139,130, filed May 2, 2002, entitled “WirelessSystem Base Station to Base Station Synchronization,” PCT ApplicationNo. US02/13710, filed May 2, 2002, entitled “Method for Load BalancingWireless Networks,” PCT Application No. US02/13879, filed May 2, 2002,entitled “Frequency Hopping Spread Spectrum Wireless SystemsInterference Mitigation by Transmit Suppression,” PCT Application No.US02/13889, filed May 2, 2002, entitled “Visual Base Station WirelessLink Quality Indicator,” and U.S. patent application Ser. No.10/218,178, filed Aug. 12, 2002, entitled “Virtual Linking Using aWireless Device,” each currently pending and each herein incorporated inits entirety by reference. Aspects of the invention can be modified, ifnecessary, to employ the systems, functions and concepts of the variousreferences described above to provide yet further embodiments of theinvention. The various embodiments can also be combined to providefurther embodiments.

The above detailed descriptions of embodiments of the invention are notintended to be exhaustive or to limit the invention to the precise formdisclosed above. While specific embodiments of, and examples for, theinvention are described above for illustrative purposes, variousequivalent modifications are possible within the scope of the invention,as those skilled in the relevant art will recognize. For example, whilesteps or components are presented in a given order, alternativeembodiments may perform routines having steps or components in adifferent order. The teachings of the invention provided herein can beapplied to other systems, not necessarily the network communicationsystem described herein. The elements and acts of the variousembodiments described above can be combined to provide furtherembodiments and some steps or components may be deleted, moved, added,subdivided, combined, and/or modified. Each of these steps may beimplemented in a variety of different ways. Also, while these steps areshown as being performed in series, these steps may instead be performedin parallel, or may be performed at different times.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” Words in the above detailed descriptionusing the singular or plural number may also include the plural orsingular number respectively. Additionally, the words “herein,” “above,”“below,” and words of similar import, when used in this application,shall refer to this application as a whole and not to any particularportions of this application. When the claims use the word “or” inreference to a list of two or more items, that word covers all of thefollowing interpretations of the word: any of the items in the list, allof the items in the list, and any combination of the items in the list.

The teachings of the invention provided herein can be applied to othersystems, not necessarily the system described herein. These and otherchanges can be made to the invention in light of the detaileddescription. The elements and acts of the various embodiments describedabove can be combined to provide further embodiments.

All of the above patents and applications and other references,including any that may be listed in accompanying filing papers, areincorporated herein by reference. Aspects of the invention can bemodified, if necessary, to employ the systems, functions, and conceptsof the various references described above to provide yet furtherembodiments of the invention.

These and other changes can be made to the invention in light of theabove detailed description. While the above description details certainembodiments of the invention and describes the best mode contemplated,no matter how detailed the above appears in text, the invention can bepracticed in many ways. Details of the protocol, data model, andprocessing scheme may vary considerably in its implementation details,while still being encompassed by the invention disclosed herein. Asnoted above, particular terminology used when describing certainfeatures, or aspects of the invention should not be taken to imply thatthe terminology is being re-defined herein to be restricted to anyspecific characteristics, features, or aspects of the invention withwhich that terminology is associated. In general, the terms used in thefollowing claims should not be construed to limit the invention to thespecific embodiments disclosed in the specification, unless the aboveDetailed Description section explicitly defines such terms. Accordingly,the actual scope of the invention encompasses not only the disclosedembodiments, but also all equivalent ways of practicing or implementingthe invention under the claims.

While certain aspects of the invention are presented below in certainclaim forms, the inventors contemplate the various aspects of theinvention in any number of claim forms. For example, while only oneaspect of the invention is recited as embodied in a computer-readablemedium, other aspects may likewise be embodied in a computer-readablemedium. Accordingly, the inventors reserve the right to add additionalclaims after filing the application to pursue such additional claimforms for other aspects of the invention.

We claim:
 1. A distributed access point, comprising: a radio node of aplurality of radio nodes configured to communicate with a client, theradio node comprising a set of radio frequency layer components and afirst remote communication component; and a controller node configuredto be remotely located relative to the radio node, the controller nodecomprising a set of access point software layer components and a secondremote communication component that is configured to establish a firstremote communication link with the first remote communication componentof the radio node for communication with the radio node, wherein thecontroller node is configured to communicate with the plurality of radionodes via remote communication links established between the secondremote communication component and respective first communicationcomponents of the plurality of radio nodes and communicate with theclient only via at least one radio node of the plurality of radio nodes;and wherein the radio node and the controller node together areconfigured to provide an intended functionality of the distributedaccess point, wherein the first remote communication component and thesecond remote communication component configured to establish a tunnelconfigured to carry a digitized form of RF data as a relay of a bitstream between an RF layer and a baseband layer that is configured tohandle either 802.11 or Bluetooth baseband protocol.
 2. The distributedaccess point of claim 1, wherein one of the radio node or the controllernode further comprises a set of physical layer components.
 3. Thedistributed access point of claim 1, wherein one of the radio node orthe controller node further comprises a set of medium access control(MAC) layer components.
 4. The distributed access point of claim 1,wherein the controller node includes a set of physical layer componentsand a set of medium access control (MAC) layer components.
 5. Thedistributed access point of claim 1, wherein the remote communicationlink is a wireless communication link, a short-range wirelesscommunication link, a BLUE-TOOTH link, or a wired link.
 6. Thedistributed access point of claim 1, wherein each of the radio node andthe controller node comprises a remote link driver configured to providethe remote communication link by extending a bus or using a protocolstack tunnel between corresponding components of the radio node and thecontroller node.
 7. The distributed access point of claim 1, whereineach of the plurality of radio nodes includes a corresponding set ofradio frequency layer components and a corresponding first remotecommunication component, each of the plurality of radio nodes configuredto provide a respective client of a plurality of clients, access to thecommunication network via the same controller node.
 8. The distributedaccess point of claim 7, wherein the radio node is further configured toestablish a corresponding remote communication link with the controllernode such that the controller node is configured to communicate witheach of the plurality of radio nodes to provide the clientscorresponding to respective radio nodes of the plurality of radio nodes,access to the communication network.
 9. The distributed access point ofclaim 7, wherein each of the plurality of radio nodes and the controllernode corresponds to one of a plurality of distributed access points. 10.The distributed access point of claim 9, wherein the controller node isoperatively connected to a system controller that is configured tocontrol at least one of the plurality of distributed access points. 11.The distributed access point of claim 10, wherein the system controlleris implemented as a physical switch.
 12. The distributed access point ofclaim 10, wherein the system controller is logically centralized andimplemented using a physically distributed hosting function incorporatedinto at least one of the plurality of distributed access points.
 13. Asystem, comprising: a plurality of distributed access points comprisingi) a first quantity of radio nodes, each radio node comprising a set ofradio frequency layer component and a first remote communicationcomponent, the radio nodes configured to establish a communication linkwith at least one client; and ii) a second quantity of controller nodesconfigured to be remotely located relative to the radio nodes, eachcontroller node comprising a set of access point software layercomponents and a second remote communication component that isconfigured to establish a remote communication link with at least twofirst remote communication components corresponding to two radio nodesof the first quantity of radio nodes for communications with the tworadio nodes, wherein each controller node is configured to communicatewith the at least one client only via at least one radio node of thefirst quantity of radio nodes, wherein the plurality of distributedaccess points include a greater number of radio nodes than controllernodes, wherein a first remote communication component of a first radionode of the first quantity of radio nodes and a second remotecommunication component of a first controller node of the secondquantity of controller nodes configured to establish a first tunnelconfigured to carry a digitized form of RF data as a relay of a bitstream between an RF layer and a baseband layer that is configured tohandle either 802.11 or Bluetooth baseband protocol and wherein a firstremote communication component of a second radio node of the firstquantity of radio nodes and the second remote communication component ofthe first controller node configured to establish a second tunnelconfigured to carry a digitized form of RF data as a relay of a bitstream between an RF layer and a baseband layer that is configured tohandle either 802.11 or Bluetooth baseband protocol; and wherein thefirst radio node and the first controller node together are configuredto provide an intended functionality of a first distributed access pointof the plurality of distributed access points and wherein the secondradio node and the first controller node together are configured toprovide an intended functionality of a second distributed access pointof the plurality of distributed access points.
 14. A distributed accesspoint for providing a client access to a communication network,comprising: a radio node configured to communicate with a client, theradio node comprising a set of radio frequency layer components and afirst remote communication component; and a controller node remotelylocated relative to the radio node, the controller node comprising a setof access point software layer components and a second remotecommunication component that is configured to establish a remotecommunication link with the first remote communication component of theradio node to communicate with the radio node, wherein the controllernode is configured to communicate with the client only via the radionode and wherein the radio node and the controller node together areconfigured to provide an intended functionality of the distributedaccess point, wherein the first remote communication component and thesecond remote communication component configured to establish a tunnelconfigured to carry a digitized form of RF data as a relay of a bitstream between an RF layer and a baseband layer that is configured tohandle either 802.11 or Bluetooth baseband protocol.
 15. The distributedaccess point of claim 14, wherein one of the radio node and thecontroller node further comprises a set of physical layer components anda set of medium access control (MAC) layer components.
 16. The system ofclaim 14, wherein the controller node does not include the set of radiofrequency layer components.
 17. The system of claim 14, wherein theradio node does not include the set of physical layer components or aset of medium access control (MAC) layer components.
 18. The distributedaccess point of claim 14, wherein the controller node is configured toestablish a plurality of communication links with remote communicationcomponents of a plurality of radio nodes remotely located relative tothe controller node.
 19. The distributed access point of claim 14,wherein the controller node includes the set of physical layercomponents and the set of medium access control (MAC) layer components.20. The system of claim 14, wherein the remote communication link is awireless communication link, a short-range wireless communication link,a BLUE-TOOTH link, or a wired link.